I have a question about the time regularity of the traces in one dimension.
Suppose I have a function space $$X = C^1([0,T];L^2(0,1))\cap C([0,T],H^1(0,1))$$ and I define an operator $E$ on $X$ by $(Ef)(t) = f(0,t).$ I know that $E$ maps $X$ to $C([0,T]).$
What can we say about $\partial_t Ef$? Where would that function live? What would be the minimal conditions on $X$ so I would have $Ef \in C^1([0,T])$.